x1, y1, x2, y2 = (float(x) for x in input().split())
print("{:.7f}".format(((x1 - x2) ** 2 + (y1 - y2) ** 2) ** 0.5)) float(x) for x in input().split() for x in input().split() x input().split() ().split () input split for x in input().split() float(x) float x x1, y1, x2, y2 = (float(x) for x in input().split()) x1 (float(x) for x in input().split()) y1 x2 y2 print("{:.7f}".format(((x1 - x2) ** 2 + (y1 - y2) ** 2) ** 0.5)) print "{:.7f}".format(((x1 - x2) ** 2 + (y1 - y2) ** 2) ** 0.5) "{:.7f}".format "{:.7f}" format ((x1 - x2) ** 2 + (y1 - y2) ** 2) ** 0.5 (x1 - x2) ** 2 + (y1 - y2) ** 2 (x1 - x2) ** 2 x1 - x2 x1 x2 2 (y1 - y2) ** 2 y1 - y2 y1 y2 2 0.5 x2, y2 = (float(x) for x in input().split()) (float(x) for x in input().split()) x2 y2 = (float(x) for x in input().split()) (float(x) for x in input().split()) y2 y1, x2, y2 = (float(x) for x in input().split()) (float(x) for x in input().split()) y1 x1, y1, x2, y2 = (float(x) for x in input().split()) (float(x) for x in input().split()) x1
x1, y1, x2, y2 = (float(x) for x in input().split())
print("{:.7f}".format(((x1 - x2) ** 2 + (y1 - y2) ** 2) ** 0.5))